“You know that each of those schools is a risk for the children who attend them,” he said.

Newsom indicated that he would sign SB 276 as soon as the companion bill passed. He signed both bills immediately after SB 714 cleared the Senate.

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“It’s our duty as a people to not obey unjust laws and we are going to march our children into the schools regardless of these unlawful laws,” said Maya Nicholls.

Leading one protest Monday was Robert Kennedy Jr., son of the former U.S. attorney general and nephew of President John F. Kennedy. As a celebrity face of the anti-vaccination movement, he argues the vaccine itself is harmful.

“It’s not these kids that are spreading this disease," he said. "Seventy-nine percent of the people who got measles this year in California were adults because the vaccine failed.”

FOX40 could not independently verify his numbers.

“We do have parents who, unfortunately, have been fed misinformation that’s caused them to be very fearful for their own children and that’s a very powerful fear if you’re afraid for your own children," Sen. Pan said.

Pan says the decision comes down to science.

“We want your child to be safe at school. We are right now experiencing the largest number of cases of measles in over 25 years,” Pan said.

It’s why some parents, like Amy Alfieri, are in support of the measure.

“I care about my own kids being safe and not being in the middle of an outbreak at school,” Amy Alfieri said.

Much of the effort started after a measles outbreak a few years back. Sen. Pan said if there are more measles outbreaks, there could be more legislation in future.